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Discussion Starter · #1 ·
Hey guys,

Yesterday I was setting up some wireless window sensors and
was having trouble after learning them in, could not get proper
response unless I was very close to the receiver. My thoughts
were that I may have had a bad receiver, so I ordered another.

Today I got a call from the customer asking if anything I did
would have effected the garage door remotes. He further explained
that the remotes would only work when it was within 2 feet of the
actual opener. I said there is NO corelation but, just to be sure
I had him power down the system by removing AC/DC so it was not powered.

There was no change in the remotes to open the OH door from a distance.
I suggested he relearn the remotes into the opener and or call
the manufacture of the opener. (Linear LD050) He called back
and said he was told by Mfg. that there was a large RF Noise
source locally and he would need a Spectrum Analyzer to determine
where it was located.

Since then he has determined that a next door neighbor has the same
problem with his remotes. Also, another close neighbor had just left
for two weeks to Europe yesterday. And that another 3 houses away,
the remotes worked just fine.

Suspicion is that the vacationing neighbor turned on something upon
leaving that is causing this RF Dead Zone.

The reason I am posting here is to ask if anyone else has experienced
this kind of issue?? And/or what household device could there be
that would create this problem??

Or does anyone have any hints how to find something that is putting
out invisible STUFF?? It would be a lot easier if it would if it
emitted a green ooze. :whistling

Thanks for any input!!

Les
 

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Capra Aegagrus
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If it's really broad-spectrum noise, you may have some luck with a cheap portable AM radio tuned to an open frequency. Their antennas are pretty directional.

Won't give pinpoint accuracy, but at the right distance from multiple points, should give a general indication of the area it's coming from.
 

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Discussion Starter · #3 ·
If it's really broad-spectrum noise, you may have some luck with a cheap portable AM radio tuned to an open frequency. Their antennas are pretty directional.

Won't give pinpoint accuracy, but at the right distance from multiple points, should give a general indication of the area it's coming from.
Thanks Tin,

I already asked if he (customer) had a portable AM radio to which
he asked can I use the one in my car?? LOL NO!!

I don't know if I even have a AM radio any more (that works)

Not sure what freq the Door Opener remotes work on but the
wireless transmitter that I was using on on 319.5mHz.

AM radio is 540 to 1600 kHz so would it even hear anything on
the mHz range??

Les
 

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Capra Aegagrus
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AM radio is 540 to 1600 kHz so would it even hear anything on the mHz range??
That's why I qualified my remarks with "broad spectrum". If it's truly noise as opposed to a strong carrier in the 300 MHz range, there should be stray subharmonics in the AM band. No way to know without trying it.

Too bad you didn't run into this 15 years ago; that's when I sold my spectrum analyzer.
 

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Discussion Starter · #6 ·
Customer called this morning and said that his remotes now work ok.
Don't know and will never know what caused the problem for two days.

Life goes on..............................
 

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I was going to suggest seeing if there was a local ham radio club and if anyone would be interested in searching for a stray RF problem. The American Radio Relay League has a book for sale to amateur radio operators or the public entitled "The RFI Handbook".

Glad it solved itself.

Sent from my SM-G930V using Tapatalk
 

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Discussion Starter · #8 ·
Yup!!
Had a call in to a friend that is a HAM operator.

He called me back today about an hour after my customer
called and said all was good.

He was very interested until I told him it went away.

I think he was a little saddened.......... :laughing:
 

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Discussion Starter · #9 ·
Hello all,

I honestly don't know WHY this stuff happens to me!! But,,,,,,,,,

Remember the above discussion from 2018 that the problem mysteriously went
away after two days??

WELL................ it came back!! Last week the customer called and
said that he had a window sensor that was not working. He then said
that they had some window cleaners in that cleaned the outside and
inside of the windows. Thought that maybe the sensor was damaged.
We tried a couple of things over the phone, nothing helped.

So I got there a few hours later. Yes, Guest Bedroom Window Right
was showing open. I checked the battery and it was at 100%.
I checked the unit with another magnet and got no response.
I then removed the sensor from the Left Window. Went to the keypad
and it shows that the zone was OK. I had the transmitter in my hand!!

Puzzled I went to the garage and looked at the LED on the Opener.
It was Solid Red. I asked the customer if the remotes work for the
garage openers?? He said NO they haven't since yesterday and his
neighbor has the same problem!! W-H-A-T!!!

I had bought a small RF Noise sensing device after the past events but it is
on my desk in my office 10 miles away and the battery needs charged.
Not that it was going to find the problem but I didn't know. Since
there was nothing I could do on site I told the customer I would
charge the unit and comeback tomorrow.

Last evening customer calls and says that the keypad was beeping
with a number of sensors "Lost". All I could do was to dial
in to the system and turn off the wireless zones. So I did.

Called him back and he said the beeping and trouble had stopped.
Which is should have.

I called him this morning and asked if anything changed. He said
that after I "turned the system off" the Garage Doors Openers worked.

What?? I didn't turn the system off. I just disabled the zones in
the system. So I dialed back in and turned the zones back on. System
showed zone 10 as being lost so I turned that one back off.

Anyhow I got there a few hours later and he said that the openers were
not working since I "turned the system back on". ????????????????????

Went to the garage and the LED's were off. He then discovered that the
GFI in the garage was tripped and the openers had no power. He reset
and the openers worked Ok. He said that there was a big storm in the
morning and a lightning strike very close. The GFI must of tripped.

As for the lost transmitter I turned it back on at the keypad and
checked the unit. Found that the battery was out of its holder and
once I re-seated it, all worked as it should.

Once again at this time 12:23pm on 6/16/2022 all was working..... AGAIN!

Also once again do not know the source of the problem!!

Also once again do not know how to find the problem to make it not
happen again!!

Once again the customer thinks that this is my fault although he has not
used those words.

Sorry for the long read............ if you read this far, thanks!!
I needed to type out the story before I lost the memory cells.

Any thoughts would be appreciated. I have re-read the thread from 2018.
I just don't know what else I can do or figure out.

MY BRAIN HURTS!!! 🥵

Les
 

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Unfortunately, intermittent problems are some if the toughest to track down. I see a few possibilities.

1) a noise source somewhere either being picked up by the base antenna or feeding in through the house electric wiring.

2) the base unit keeps trying to find a lost transmitter and it is broadcasting on the same frequency as the garage door opener, effectively jamming that signal.

If the garage door opener actually doesn't work when you lose a sensor, that would be my guess. It should be repeatable or nearly so.

Go ahead and sniff around for noise sources while you're there, you never know what you'll find.
 

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Discussion Starter · #11 ·
Unfortunately, intermittent problems are some if the toughest to track down. I see a few possibilities.

1) a noise source somewhere either being picked up by the base antenna or feeding in through the house electric wiring.

2) the base unit keeps trying to find a lost transmitter and it is broadcasting on the same frequency as the garage door opener, effectively jamming that signal.

If the garage door opener actually doesn't work when you lose a sensor, that would be my guess. It should be repeatable or nearly so.

Go ahead and sniff around for noise sources while you're there, you never know what you'll find.
The security panel receiver is just that............a receiver. It only receives the transmitted
signal from the transmitter when they are sent. Open, Close, Lo Bat. The panel then
will do as programmed and display the condition on the keypad. When it does not see
a signal from the transmitters after a period of time, the panel then reports a lost
transmitter. The same thing will happen when the signals are Jammed on that
frequency. No signals received. "Lost Transmitter(s)"

The Garage Door Opener only looks the proper encrypted signal on the receiver. It then
respond and opens the door when the right code is received. When there is excessive
Jamming on the frequency it can't see the specific encrypted code and thus will not open.

What seems to be happening is that there is a LARGE CONTINEUOS RF signal that
does not stop. Much the same as (If you remember) somebody keys a CB Mic in there
truck and does not release. Whatever frequency or channel they are on stops all
communication until the Mic is released. Because the CB radio takes preference to
that audible signal on that frequency and communicate out whatever the Mic is hearing.

What I have determined (limited) is that something in this specific area of about
7,000 square yards Is being turned on for maybe 48 +/- hours, then it is turned off.

Since it can't be seen, smelled, tasted, heard it can't be located. And since I don't have a
spectrum analyzer in my van at the time it is happen it can't be located.
(not going to buy one for this issue. $$$$)

I did call the FCC and it would have been better to talk to a blank wall.
They have their procedures and bla bla bla.

Again, i have no clue as to WHY this kind of thing happens to ME!!!

I thought I would share my experience on this bizarre thing. It also puts me into the
thinking of a Sci-Fi movie script. Like maybe "Resident Alien" of something. Needless
to say I will not be auditioning for the part in the show, BUT, royalties might be nice!!!

Thanks for any thoughts. Although since [ IT ] is gone at this time nothing can be done.

If it ain't broke, you can' fix it!!! And now, even if it is broke I can't find it to fix it!!!

Les
 

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Les:
You did not say what your business is or how you are involved in this situation.
In the OP you said you were setting up some window sensors. Are you in the business of installing and servicing alarm systems? Did you sell and install this system? If so, I would hope you have the necessary equipment and expertise to diagnose and correct this type of issue. It's neither uncommon nor un-solvable. The tech department of your system manufacturer can help steer you in the right direction. They also often have field reps who can take a look at highly unusual problems with their equipment. The FCC is about the last place to ask.

As I'm sure you figured out by now, getting involved is not a good idea unless you have the equipment and expertise to solve the problem. EMI/RFI issues can be difficult to solve and do require a higher level of expertise. While a spectrum analyzer may help, it's not necessary. There are less expensive tools and methods. You just need to have a good, solid diagnostic procedure and go through it step by step. Most manufacturers have such a procedure or can help you devise one.

If you are a GC and provide alarm systems as part of bigger projects, I would highly recommend having a qualified specialty sub handle it for you.
 

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If this happens every 4 years, it isn't likely to be found. It could be anything from a source outside the home to wiring issues or issues with one or more loads. While it's happening, the instrumentation needed is relatively cheap, but since it is very infrequent , this would be 2 sets of recording instrumentation, and those aren't cheap.

You've verified proper operation of the system. The door opener indicates a common cause - not your problem.

That's about all you can personally do.
 

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Discussion Starter · #15 ·
Les:
You did not say what your business is or how you are involved in this situation.
In the OP you said you were setting up some window sensors. Are you in the business of installing and servicing alarm systems? Did you sell and install this system? If so, I would hope you have the necessary equipment and expertise to diagnose and correct this type of issue. It's neither uncommon nor un-solvable. The tech department of your system manufacturer can help steer you in the right direction. They also often have field reps who can take a look at highly unusual problems with their equipment. The FCC is about the last place to ask.

As I'm sure you figured out by now, getting involved is not a good idea unless you have the equipment and expertise to solve the problem. EMI/RFI issues can be difficult to solve and do require a higher level of expertise. While a spectrum analyzer may help, it's not necessary. There are less expensive tools and methods. You just need to have a good, solid diagnostic procedure and go through it step by step. Most manufacturers have such a procedure or can help you devise one.

If you are a GC and provide alarm systems as part of bigger projects, I would highly recommend having a qualified specialty sub handle it for you.
Gee Whiz G&Co.,

I have been a member here since 2005 about 15 years longer that you. At this point in
time I didn't think I needed to detail my back ground and expertise or lack thereof.

However, I am a security dealer and have been for going on 33 years.
I am a small LLC company corporation consisting of ................... just me!!!
I was installing a security system for the home owner when this whole thing first appeared.
And then it was gong.............and then it came back...............and then it is gone.
For the duration of when it was there certainly was not enough time to get any "expert"
to respond to find the problem.

As for getting involved?? Well I don't how I would not be getting involved. It is my customer
that is being affected by something abnormal.

I posted the issue here for a number of reasons. Three of which I will type out.
1) To see if any others may have similar situations and what they may have done about it.
2) To see if any others had any thoughts that I could use to help understand and solve the problem.
3) To help someone in the future that may read this now and know they are not alone.

All that being said; Thanks for your comments and life goes on.

Have a good day.

Les
 

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Discussion Starter · #16 ·
If this happens every 4 years, it isn't likely to be found. It could be anything from a source outside the home to wiring issues or issues with one or more loads. While it's happening, the instrumentation needed is relatively cheap, but since it is very infrequent , this would be 2 sets of recording instrumentation, and those aren't cheap.

You've verified proper operation of the system. The door opener indicates a common cause - not your problem.

That's about all you can personally do.
Hi hdavis,

Yes you are right. The door opener is not my problem. However, it is a indicator
or tool to show that the problem is larger than just a security panel not working
properly. If it was not for the opener issue affecting both my customer as well
as the neighbors this would have a whole different picture.

Thanks,

Les
 

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Capra Aegagrus
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Sounds like there was some miscommunication and/or coincidence muddying up the works. If I understand you correctly, the security system maybe had a hiccup (not counting the loose battery) that you routinely addressed and cleared. The garage door opener is a separate issue with a popped GFCI. That one's on the HO.

As for spectrum analyzers, line quality recorders and such, they can be rented fairly reasonably.
 

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Hi hdavis,

Yes you are right. The door opener is not my problem. However, it is a indicator
or tool to show that the problem is larger than just a security panel not working
properly. If it was not for the opener issue affecting both my customer as well
as the neighbors this would have a whole different picture.

Thanks,

Les
That's what common cause means. Noise messing up both the opener and the security system.
 

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If you have a service contract with them, do whatever your contractual obligation is. If you don't, bow out.

The more you try to help them with this, the more they'll act like 4 years later this is your problem to solve.
 

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Discussion Starter · #20 ·
Sounds like there was some miscommunication and/or coincidence muddying up the works. If I understand you correctly, the security system maybe had a hiccup (not counting the loose battery) that you routinely addressed and cleared. The garage door opener is a separate issue with a popped GFCI. That one's on the HO.

As for spectrum analyzers, line quality recorders and such, they can be rented fairly reasonably.
Hi Tin,

The GFCI popping was due to a storm at the wrong time. It was only noticed by the homeowner
when I was there and after the RF issue had stopped.
BTW I think it is rather odd to have the Openers powered off a GFCI. If you were away and there was
a storm or moisture or something that caused it to trip you are then challenged to get into your house.
Then again it is not my thing and maybe it is NEC code today??

As for the loose battery. This may have happened with the window cleaners. During the time that the
RF noise was happening it was not noticed by the panel since is was not seeing anything. Once
it was gone and I turned the zone back on they it showed up on the keypad.

As for renting a Spectrum Analyzer............................
Well lets just say the problem won't return................................

Thanks,

Les
 
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